This invention relates generally to binders for holding an accumulation of hole-punched pages of ruled or unruled paper of the type used by school students and office personnel. In a more specific aspect the invention pertains to a process for fabricating a flat, relatively rigid, polyolefin sheet for use by binder producers. In still another of its aspects the invention provides a blank for use in fabricating one-piece loose-leaf binder covers by a two-up process which minimizes the fabrication steps required of binder manufacturers.
It has become the practice of discount merchandisers and others distributing school supplies and office supplies to offer reasonably priced plastic binders along with the inexpensive ruled or unruled notebook paper which is widely used in schools at all levels for note taking purposes as well as storing records in offices. A variety of such binders are known in the art for holding an accumulation or collection of pages for student and business use. These binders can generally be divided into three major classes: those with snap ring binding mechanisms; those with adjustable height stud type binders; and the folding stud or post type of binder mechanism, the binder mechanism being the paper holding device which is secured to the back or edge panel within the binder. The back, or edge, panel is usually termed a spine. Still another type of binder mechanism employs a pressure clamp.
Probably the most widely used binding mechanism is the snap ring binding mechanism in which sets of two generally semicircular fingers, which are spring loaded and mounted to a metal base, can be closed to produce a substantially circular ring which passes through holes punched in the edges of the binder paper. There is usually one such ring for each hole punched in the binder paper.
It will be appreciated that binders with leather and plastic covers surrounding stiff cardboard front, rear and spine panels are relatively expensive due to the cost of construction. As illustrated in such patents as U.S. Pat. Nos. 4,307,972 and 5,878,946 the trend is to cut the cost of the item by utilizing plastic binder covers. As described in U.S. Pat. No. 5,618,122, even the ring binding mechanism of the binder may be fabricated using plastics. The trend, then, is to provide an inexpensive binder through the use of one-piece plastic cover fabrication processes. To this end a blank is provided for use by binder fabricators or converting companies. In the past such companies have purchased partially fabricated thermoplastic panels and by cutting and scoring have made one-piece binder covers in which they could install the paper-holding ring binding mechanism.
This invention provides improvements in the blank forming process in a manner not revealed in the known prior art.
This invention provides blanks and a process to facilitate manufacturing a looseleaf binder. It is an object of the invention to reduce the number of processing steps required of the converting companies, thereby lowering the cost of fabrication of binders. An additional object of the invention is to provide a binder material which can be readily decorated by screen printing and the like. Still another object of the invention herein is to provide a simple, inexpensive, looseleaf binder for holding the binding mechanism and the sheets of paper and the like, therein, having holes punched at a specific spacing along one edge. It is a further object of the invention to provide binders having unitary plastic covers of various thicknesses with pre-scored fold or hinge lines which permit folding of the front and rear covers relative to the spine.
This invention pertains to a two-up process for manufacturing one-piece covers for loose-leaf binders or notebooks which removably receive and hold hole-punched binder paper sheets. The binder cover is fabricated from a panel or blank of an extruded polyolefin material. The blank is cut in the shape of a quadrilateral having perpendicular adjacent sides providing opposed pairs of parallel sides. In other words the blank is a rectangular or square sheet of plastic having opposed parallel sides. Midway between two of its parallel sides the blank is perforated to form a separation line resulting in two rectangles connected together by the perforated separation line. A recess is cut in the blank at each end of the perforated separation line resulting in two rectangles each having four exposed corners. The rectangles thus each have one long peripheral edge and two short peripheral edges, with the other long peripheral edges of each rectangle being formed upon separation of the two rectangles along the perforation line. Prior to separation the four exposed corners of each of the two rectangles are rounded off. At least one pair of fold or hinge lines perpendicular to the perforated separation line is formed across the rectangles to define equally sized front and rear binder panels and a smaller spine panel between them in the form of a binder back panel for attachment thereto of a paper holder which will hold the pages of paper. Typically, the holder will provide a three-ring binding mechanism.
These and other objects and advantages, as well as the invention itself, will become more apparent if the invention is summarized and described in greater detailed by reference to drawings.